We have previously written about ‘overdiagnosis’ – the diagnosis of an illness that would never have caused symptoms or death had it remained undetected – and how the majority of the public are unfamiliar with the concept and find it difficult to understand. We have also looked at the various ways that health websites describe it in the context of breast cancer screening; we previously found that most UK websites include some relevant information, in contrast to the last similar study from 10 years ago. This led us to think about how it might be possible to better explain the concept to people. Although ‘overdiagnosis’ is the most commonly used label, its meaning is probably difficult to infer if people are unfamiliar with it (and most people are). We wanted to test whether other terms might be seen as more intuitive labels that would help communicate the concept to the public.

We carried out a large survey in which we asked around 2,000 adult members of the public to read one of two summaries describing overdiagnosis. These summaries were based on information leaflets that the NHS has already used extensively in England. We asked people whether any of a series of possible alternative terms made sense to them as a label for the concept described and whether they had encountered any of the terms before.

What did we find?

A fairly large proportion of people (around 4 out of 10) did not think any of the seven terms we suggested were applicable labels for the concept as we described it. We also found that no single term stood out as being seen as particularly appropriate. The term most commonly endorsed (“unnecessary treatment”) was only rated as appropriate by around 4 out of 10 people. Another important finding was that around 6 out of 10 people had never encountered any of the terms we suggested and that the most commonly encountered term (“false positive test results”) was only familiar to around 3 out of 10 people. You can read the full paper here.

What were our conclusions?

We were disappointed that we did not find a term that was clearly considered to be an intuitive label for the concept of overdiagnosis. However, this was not entirely surprising because we know fromseveralstudies that it is unfamiliar to most people. It is not a given that this will always be the case: Organisations like the NHS and health charities are continually telling the public about overdiagnosis in various ways and if the concept becomes more familiar and better understood, people may be more inclined to identify a term that makes sense and which can then be used to communicate the concept. It is also possible that terms other than the 7 we looked at might already be suitable. Since the terms we looked at were generally unfamiliar, one recommendation we can make in the meantime is that it might be better to avoid specific labels like “overdiagnosis” when communicating the issue to people; explicit descriptions might be more helpful.

Cancer screening programmes, such as breast, cervical, and bowel, are an important tool in the fight against cancer. Many people are aware of the value of early detection of cancer, which breast screening and the Faecal Occult Blood test (FOBt) part of bowel screening offer, which allows for treatment at an earlier stage when it is more likely to be effective. But are people aware that cervical screening and bowel scope screening (also known as flexible sigmoidoscopy, or FS) primarily aim to prevent cancer by identifying and removing abnormalities which may progress into cancer at a later date? This is the question we looked to answer in our recently published paper1 in the Journal of Medical Screening.

As part of a larger survey on attitudes and behaviours surrounding cancer, we asked 1433 middle aged and older adults what they thought the main purpose of each of these screening programmes was. We found that while the majority of respondents were aware that breast screening (77.9%) and FOBt (73.2%) aimed to detect cancer early, only 17.6% knew that cervical screening primarily aimed to prevent cancer. For bowel scope screening the figure was only 13.8%. Overall only 13 people correctly identified the purpose of all four screening programmes, which is just under 1% of respondents.

We also looked at whether people had participated in each programme in the past to see whether that had any effect on awareness of the purpose of the programme. People who had been sent a test kit, and those who had completed and returned the kit were more likely to know that FOBt is designed to detect cancer early. For breast screening, only those having participated in screening were more likely to know that it was aimed at early detection. Having received an invitation did not seem to have an effect on knowledge of the purpose of the test.

However for both cervical screening and bowel scope screening neither those who had received an invitation nor those who had actually participated in the programme were any more likely to be aware of the preventive nature of the programme than respondents who hadn’t been invited or participated. This is despite the leaflets accompanying invitations clearly stating prevention as the main purpose.

On the one hand it is positive that public health messages on the importance of the early detection of cancer have been so effective, and that the majority of people recognise this to be the purpose of breast screening and FOBt. However, for people to make an informed choice about whether to participate in a screening programme they need an understanding about what the screening test aims to do, as well as any risks and benefits. Our survey suggests that this is not the case for cervical screening and bowel scope. As well as this lack of awareness being an issue for informed choice, it could also have consequences for how people engage with the screening programmes. People may end up avoiding screening tests if they are afraid they might be told they have cancer2, 3. Knowing that some programmes can prevent cancer by finding and removing abnormalities may help to reduce these fears. Other studies have shown that women invited to colposcopy after having an abnormal result from their smear test sometimes mistakenly believe they have cancer4, 5. A better awareness that cervical screening mainly looks for cell abnormalities which can be removed before they have a chance to turn into cancer may help in reducing stress and worry about the abnormal result.

If leaflets aren’t getting these messages across effectively, one of the priorities for the future will be finding different ways to communicate about cancer screening so that everyone understands what the tests are trying to do.

Andersen MR, Smith R, Meischke H, Bowen D and Urban N. Breast cancer worry and mammography use by women with and without a family history in a population-based sample. Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology. 2003; 12: 314-20.

Today at the NCRI Cancer Conference in Liverpool, the inaugural Jane Wardle prize was awarded to our very own Dr Jo Waller to recognise her world-leading contribution in cervical cancer prevention. The prize was set up by Cancer Research UK in memory of Professor Jane Wardle who died last year. Jo has been at the Health Behaviour Research Centre for 15 years and was herself mentored by Jane Wardle. In this blog we highlight some of Jo’s key research in cervical cancer prevention during this time.

In 2005, Jo completed a PhD exploring psychosocial issues surrounding the viral aetiology of cervical cancer. These early studies explored the emotional and social consequences of a HPV diagnosis and how women make sense of a HPV positive result at cervical screening. The findings highlighted extremely low awareness of HPV and poor understanding about how cervical cancer develops. This work also showed the importance of providing good information to ensure minimal anxiety when receiving a HPV positive result at screening and to avoid stigmatising cervical cancer.

Jo and her colleagues went on to explore psychosocial issues surrounding HPV vaccination before and after its introduction in 2008. This research helped identify the most appropriate age for the vaccine and contributed to the content of the information materials provided. In addition, this work offered reassurance that vaccination against a sexually transmitted infection (the HPV vaccine) did not result in changes to girls’ sexual behaviour as some media reports had suggested. Jo’s work has also explored why certain sub-groups of the population, such as young women and ethnic minority women are less likely to participate in cervical screening.

In 2014, Jo was awarded a prestigious Cancer Research UK Career Development Fellowship to continue her research in cervical cancer prevention. Jo now formally manages a team of researchers and her current research activities include understanding non-participation in cervical cancer screening and HPV vaccination, developing interventions to improve uptake of these cervical cancer control interventions, and evaluating the psychological impact of primary HPV testing within cervical screening.

Jo has also been involved in numerous other bodies of work over the last 10 years including development of the Cancer Awareness Measure and studies exploring informed choice about screening. She is also an informal mentor to many students and colleagues. We are all very proud of Jo’s achievement today. Well done Jo!

You can read more about our current work in cervical cancer prevention on our website.

We’ve written here before about the difficulty of recognising symptoms that could be signs of cancer, and knowing when it’s appropriate to go to the doctor about them. There’s lots of evidence that cancer is more treatable if it’s found at an earlier stage, but we know less about effective ways of encouraging people to seek help appropriately.

Encouraging people to seek help

Our new study tried to do just this. We focused on gynaecological cancers – that is ovarian, cervical, endometrial (womb/uterine), vaginal and vulval cancers which together affect over 20,000 women a year in the UK. We know from previous research that some of the things that stop people going to the doctor with symptoms are:

1) Not knowing that the symptom could be a sign of something serious
2) Worry about wasting the doctor’s time
3) Embarrassment about discussing or exposing intimate parts of the body
4) Worry about what the doctor might find

So we designed an information leaflet that addressed some of these issues. It provided details about possible symptoms of gynaecological cancer and a checklist to help women record their symptoms and make a plan to visit their GP. It reassured women that their doctor would be happy to see them, and that the symptoms were unlikely to be serious. It addressed the issue of embarrassment and reminded women they could ask to see a female doctor.

In this study , we used questionnaires to measure the impact of the leaflet in the short-term. We asked 464 women about their symptom knowledge, the things that might put them off going to the doctor if they had gynaecological symptoms, and how quickly they thought they would seek help for a range of symptoms. We also asked about how anxious they were feeling right now, so we could see if the leaflet raised anxiety levels. Women then spent some time reading the leaflet before filling in another questionnaire.

What did we find?

After reading the leaflet, most women said they would seek help more quickly if they noticed one of the symptoms. In particular, we reduced the number of women who said they would never seek help for vague symptoms like bloating and feeling full quickly, which can be signs of ovarian cancer. Women reported fewer barriers to visiting their GP, and greater knowledge about possible symptoms of gynaecological cancer. There was no evidence that the leaflet made women feel anxious.

What next?

These findings are very encouraging, and suggest that a leaflet may be an effective way of promoting prompt help-seeking for these symptoms. But it’s also important to remember that it was an experimental study – women read the leaflet under controlled conditions, so it doesn’t tell us what impact the leaflet would have in a real-world setting where women might be sent it in the post, or handed it at their GP surgery. Under these circumstances, they might not even read it.

In addition, we could only measure women’s anticipated help-seeking, and we can’t be sure what they would really do if they had these symptoms. Even when people intend to seek help, life often gets in the way, other things take priority, and people don’t get round to making an appointment.

The next step will be to see what happens when we actually send the leaflet to women – will more of them seek help and, ultimately, will more cancers be diagnosed at an earlier stage when treatment is more effective? We hope to answer these questions in our future work.

In our last blog, we talked about ‘overdiagnosis’, a concept that many people are unfamiliar with – that is, when a medical test finds an illness that would never have caused any harm during a person’s lifetime.

As a follow-up study, we were interested in how much information the UK and Australian public could find online about overdiagnosis in the specific context of breast cancer screening.

Why breast cancer screening?

We chose breast screening because it is a setting in which the issue of overdiagnosis has received a lot of attention in the UK in recent years: in 2011, Cancer Research UK and the Department of Health commissioned a review of studies with the aim of understanding how much overdiagnosis happens in breast screening.

Likewise, the NHS recently made substantial changes to the information leaflets provided to women invited for breast screening, with the aim of ensuring that they would understand that overdiagnosis was one possible outcome of being tested.

Breast screening sometimes diagnoses ‘ductal carcinoma in situ’ or ‘DCIS’, which is an abnormality that can become a symptomatic cancer over time. However, it can also be slow growing and never pose a health risk, meaning that a large proportion of overdiagnosis in breast screening is due to DCIS.

As well as finding out what kind of information people could find about overdiagnosis on health websites, we were interested in what explanations those websites provided about DCIS, and also what kinds of statistics were used to give the public a sense of how many people are affected by overdiagnosis.

We used a Google search for ‘breast cancer screening’ to find the most relevant health websites in the UK and Australia (such as NHS Choices and Cancer Australia). We examined in detail ten websites from the UK and eight from Australia.

What did we find?

Our main findings were that most UK websites included some information about overdiagnosis and also DCIS. The websites provided a range of statistics stating, for example, that every year around 4,000 women in the UK are overdiagnosed and overtreated following screening and that around 3 in 200 women screened would be overdiagnosed and overtreated (considering women aged between 50 and 70 years undergoing screening every three years).

Such information was available less often on Australian websites, although the kind of information was similar when it was present (and several websites linked to more detailed websites instead of hosting the information themselves).

Why is this important?

One reason for doing this research was that a similar study had been carried out more than ten years ago in 2000, showing that overdiagnosis and DCIS were rarely described. We thought that things might have changed in the meantime as more and more people use the internet to understand health issues.

In fact, we found that although not every piece of information on overdiagnosis and DCIS is available on every website, it is more available than it was in the past. In time, this might lead to a greater level of public awareness about the issue.

In recent years, doctors and academics have become more and more interested in a problem referred to as ‘overdiagnosis’. There are several ways that overdiagnosis can be defined.

One particularly useful way is to think of it as the diagnosis of a disease that would never have caused a person symptoms or led to their death, whether or not it had been found through a medical test. In other words, even if a person had not had the test, the disease would never have caused them any harm.

Catching it early

It may not be obvious how this can happen. As an example, imagine a woman going for breast screening, which tries to find cancer at an early stage, before it starts causing symptoms.

The thinking behind this type of test is that if the disease is found early, it will be easier to treat and there is a higher chance of curing it. Most people are familiar with this idea that ‘catching it early’ is a good thing.

So, suppose a woman who has no symptoms goes for screening and the test finds cancer: she would usually go on to have treatment (e.g. surgery).

However, although she has no way of knowing for sure, it is possible that the cancer was growing so slowly that she would have lived into old age and died of something unrelated, without ever knowing about the cancer, had she not gone for screening.

The cancer is real but the diagnosis does not benefit the woman at all; it results in treatment that she did not need (‘overtreatment’). In fact, if she had not had the screening test, she would have avoided all the problems that come with a cancer diagnosis and treatment.

What research has found

If you find the idea of overdiagnosis counter-intuitive, you are not alone. Several studies have tried to gauge public opinion on the issue and found that this is a fairly typical view, partly because the notion that some illnesses (like cancer) might never cause symptoms or death is one that does not receive much attention and is often at odds with our personal experiences.

Results from an Australian study in 2015 found that awareness of ‘overdiagnosis’ is low – in a study of 500 adults who were asked what they thought it meant, only four out of ten people gave a description of the term that was considered approximately correct and these descriptions were often inaccurate to varying degrees.

For example, people often thought in terms of a ‘false positive’ diagnosis (diagnosing someone with one illness when really they do not have that illness at all), or giving a person ‘too many’ diagnoses.
Is this the same in the UK?

We wanted to find out whether this was also true in the UK. We asked a group of 390 adults whether they had come across the term ‘overdiagnosis’ before and asked them to describe what they thought it meant in their own words, as part of an online survey.

We found that only a minority (three out of ten people) had encountered the term and almost no-one (10 people out of all 390) described it in a way that we thought closely resembled the concept described above.

It was not always clear how best to summarize people’s descriptions but we found that people often stated that they had no knowledge or had similar conceptions to the Australian survey such as ‘false positives’ and ‘too many’ diagnoses.

Some descriptions were somewhat closer to the concept of overdiagnosis such as an ‘overly negative or complicated’ diagnosis (e.g. where the severity of an illness is overstated) but there were also some descriptions that we found more surprising such as being overly health-conscious (e.g. worrying too much about health issues).

Room for improvement

Many people who work in public health and healthcare believe that people should be aware of the possibility of overdiagnosis, particularly since they will eventually be offered screening tests in which there is this risk.

In this respect, our findings show that there is substantial room for improvement in how we inform the public about overdiagnosis. In part, this may be due to the term itself not having an intuitive meaning, in which case other terms might be more helpful (for example the term ‘unnecessary detection’).

This could be tested in future studies. Our findings also motivated us to find out the extent to which trusted information sources (such as websites run by the NHS and leading health charities) are already providing information on overdiagnosis.

We would like to share the findings from this study in a follow-up blog post. We will be posting this here soon.

We recently wrote an editorial in Cancer Epidemiology on this very topic, commenting on a new population-based study looking at delays in the diagnosis (and treatment) of lung cancer in elderly patients in the US. The study was based on linked routine healthcare data (SEER-Medicare to be specific) collected on nearly 50,000 US patients. There are a few key findings that we highlight in the editorial:

The median diagnostic interval (the time between when a patient first presents with symptoms and diagnosis) was around 180 days (almost 6 months). This means that more than half of the patients in this study had a diagnostic interval of longer than 6 months, which is a pretty alarming finding. Similar findings have been published in England recently, showing how difficult it can be to detect and diagnose lung cancer.

Older patients had longer median diagnostic intervals than younger patients, and women had longer diagnostic intervals than men. Again, similar patterns have been described before in the UK, but the inequalities found by this study were particularly large and clearly further research is needed in this area.

There were also delays from diagnosis to treatment, which were much shorter than the diagnostic interval (27 and 18 days for patients with non-small cell and small cell lung cancer respectively). Patient characteristics didn’t have much effect on the length of the treatment interval, compared to the diagnostic interval. In other words, once a diagnosis of lung cancer was made, the patient’s age, sex, race, and comorbidity status (whether they had other health conditions) didn’t influence their time to treatment much.

Relatedly, specialist investigations are increasingly being used to inform treatment options, including PET-CT imaging and biomarker profiling. Unfortunately such advances in personalising cancer care also have the potential to delay the start of treatment. Although challenging, this may be seen as an opportunity to streamline and integrate cancer care pathways and services.

Overall, the findings of the US study add to the growing body of evidence on diagnostic delays in cancer from the UK and other countries, clearly indicating that this is a global problem that transcends countries and healthcare systems. Building on the shared learning generated by the ICBP, future international efforts in cancer outcomes research should aim to include US patients in order to bring further insights into the cause of such delays. By first asking “why” the delays occur, we can then turn to the “how” and “what” we can do about these universal problems.

In our recent paper we studied how pre-diagnosis experience affects subsequent care experience in cancer patients (1). Our findings suggest that patients who experienced more pre-referral consultations in primary care are more likely to be less satisfied with their care. As perhaps could have been expected, the associations found were stronger for questions involving primary care compared to hospital care.

We used data from over 70,000 patients who responded to the English Cancer Patient Experience Survey. In this survey patients report the number of pre-referral consultations with a GP, which was used as a marker of diagnostic delay. As different patients may vary in their tendency to give critical responses in general, we adjusted our analysis using a response tendency item. This item was calculated using mixed effects models and included responses to several questions from the survey.

This work further supports efforts aimed at reducing time to diagnosis and amplifies previous evidence where patients expressed preference for having cancer investigations at low risk levels (2).

The fact that associations found were stronger for aspects involving primary care has implications for follow up involving general practice.